add reset view button

src/app.zig

@@ -22,8 +22,6 @@ const max_files = 32;
 
 const FileChannel = struct {
     path: []u8,
-    min_value: f64,
-    max_value: f64,
     samples: []f64,
 
     fn deinit(self: FileChannel, allocator: std.mem.Allocator) void {
@@ -42,8 +40,6 @@ const DeviceChannel = struct {
     units: i32 = NIDaq.c.DAQmx_Val_Volts,
     min_sample_rate: f64,
     max_sample_rate: f64,
-    min_value: f64,
-    max_value: f64,
 
     active_task: ?*TaskPool.Entry = null,
 
@@ -57,7 +53,12 @@ const ChannelView = struct {
     view_rect: Graph.ViewOptions,
     follow: bool = false,
 
-    height: f32 = 150,
+    height: f32 = 200,
+
+    default_from: f32,
+    default_to: f32,
+    default_min_value: f64,
+    default_max_value: f64,
 
     source: union(enum) {
         file: usize,
@@ -262,22 +263,24 @@ pub fn appendChannelFromFile(self: *App, path: []const u8) !void {
     const loaded_file_index = findFreeSlot(FileChannel, &self.loaded_files) orelse return error.FileLimitReached;
 
     self.loaded_files[loaded_file_index] = FileChannel{
-        .min_value = min_value,
-        .max_value = max_value,
         .path = path_dupe,
         .samples = samples
     };
     errdefer self.loaded_files[loaded_file_index] = null;
 
-    const margin = 0.1;
+    const from: f32 = 0;
-    const sample_range = max_value - min_value;
+    const to: f32 = @floatFromInt(samples.len);
     self.channel_views.appendAssumeCapacity(ChannelView{
         .view_rect = .{
-            .from = 0,
+            .from = from,
-            .to = @floatFromInt(samples.len),
+            .to = to,
-            .min_value = min_value - sample_range * margin,
+            .min_value = min_value,
-            .max_value = max_value + sample_range * margin
+            .max_value = max_value
         },
+        .default_from = from,
+        .default_to = to,
+        .default_min_value = min_value,
+        .default_max_value = max_value,
         .source = .{ .file = loaded_file_index }
     });
     errdefer _ = self.channel_views.pop();
@@ -310,8 +313,6 @@ pub fn appendChannelFromDevice(self: *App, channel_name: []const u8) !void {
         .name = name_buff,
         .min_sample_rate = ni_daq.getMinSampleRate(channel_name_z) catch max_sample_rate,
         .max_sample_rate = max_sample_rate,
-        .min_value = min_value,
-        .max_value = max_value,
         .samples = std.ArrayList(f64).init(self.allocator)
     };
     errdefer self.device_channels[device_channel_index] = null;
@@ -323,6 +324,10 @@ pub fn appendChannelFromDevice(self: *App, channel_name: []const u8) !void {
             .min_value = min_value,
             .max_value = max_value
         },
+        .default_from = 0,
+        .default_to = 0,
+        .default_min_value = min_value,
+        .default_max_value = max_value,
         .source = .{ .device = device_channel_index }
     });
     errdefer _ = self.channel_views.pop();
@@ -499,6 +504,8 @@ fn showChannelView(self: *App, channel_view: *ChannelView) !void {
     source.lockSamples();
     defer source.unlockSamples();
 
+    var channel_rect_opts: *Graph.ViewOptions = &channel_view.view_rect;
+
     const channel_box = self.ui.newBoxFromPtr(channel_view);
     channel_box.background = rl.Color.blue;
     channel_box.layout_axis = .Y;
@@ -516,6 +523,18 @@ fn showChannelView(self: *App, channel_view: *ChannelView) !void {
         self.ui.pushParent(tools_box);
         defer self.ui.popParent();
 
+        {
+            const reset_view_button = self.ui.button(.text, "Reset view");
+            reset_view_button.size.y = UI.Size.percent(1, 0);
+
+            if (self.ui.signalFromBox(reset_view_button).clicked()) {
+                channel_rect_opts.from = channel_view.default_from;
+                channel_rect_opts.to = channel_view.default_to;
+                channel_rect_opts.min_value = channel_view.default_min_value;
+                channel_rect_opts.max_value = channel_view.default_max_value;
+            }
+        }
+
         if (source == .device) {
             const device_channel = source.device;
 
@@ -542,8 +561,8 @@ fn showChannelView(self: *App, channel_view: *ChannelView) !void {
                                 .continous = .{ .sample_rate = device_channel.max_sample_rate }
                             },
                             .{
-                                .min_value = device_channel.min_value,
+                                .min_value = channel_view.default_min_value,
-                                .max_value = device_channel.max_value,
+                                .max_value = channel_view.default_max_value,
                                 .units = device_channel.units,
                                 .channel = channel_name
                             }
@@ -571,8 +590,6 @@ fn showChannelView(self: *App, channel_view: *ChannelView) !void {
     }
 
     {
-        var channel_rect_opts: *Graph.ViewOptions = &channel_view.view_rect;
-
         const graph_box = self.ui.newBoxFromString("Graph");
         graph_box.flags.insert(.clickable);
         graph_box.flags.insert(.draggable);